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Monthly average snow depth

Question asked by Jamisa on Jan 8, 2016
Latest reply on May 17, 2018 by AyeshaAnwar

I am trying to import the monthly average snow depth data for 1998-2014 from Canadian Meteorological Centre (http://nsidc.org/data/NSIDC-0447/versions/1) into ArcGIS (ArcMap 10.3). I downloaded the text files (cmc_analysis_mly_avg_1998.txt etc.) and wrote this header (as it does not have one):

 

ncols 706

nrows 706

xllcorner   -125.000000

yllcorner   0.1665461

cellsize 10

nodata_value -9999

 

I used Ascii to raster in Arc toolbox, the transformation seemed successful, and an image appeared. However the image does not look like the northern hemisphere. I also tried to define projection (tried both north pole stereographic projection and WGS1984 arctic polar stereographic projection) using Define projection in the toolbox, but in both cases the image “disappeared” (cannot not see it even when zooming to layer or raster resolution). I guess the information in my header is wrong. I suspect that at least llcorner might be a problem - I used the coordinates from row 1, column 1 in cmc_analysis_ps_lat_long.txt file.

 

Has anyone done this and have a correct header, or can someone help me understand how to write the header? It seems as I have not understood how to use the information in the CMC snow depth documentation correctly.

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